NASA will be performing network maintenance on Thursday, November 7, 2024, between 14:00 EST and 16:00 EST (19:00 UTC and 21:00 UTC). There will be two periods of about five minutes of disruption. This will result in the unavailability of the CDDIS archive and the website. If you experience problems outside this window, contact support-cddis@nasa.gov.

close window
Daily 30-second mixed broadcast ephemeris data

doi:10.5067/GNSS/gnss_daily_x_001

Data Center Citation

Noll, Carey E., The Crustal Dynamics Data Information System: A resource to support scientific analysis using space geodesy, Advances in Space Research, Volume 45, Issue 12, 15 June 2010, Pages 1421-1440, ISSN 0273-1177, http://dx.doi.org/10.1016/j.asr.2010.01.018.

Data Citation

International GNSS Service (IGS). 1992. Daily 30-Second mixed broadcast ephemeris data [online]. Available from the NASA Crustal Dynamics Data Information System DAAC, Greenbelt, MD, USA at: http://dx.doi.org/10.5067/GNSS/gnss_daily_x_001, Accessed [[enter user data access date]].

Other standard citation formats may be used for this data set and can be found at the DOI Citation Formatter website.

More information about CDDIS data citations and acknowledgments is available.

Summary

  • Name: Daily 30-second mixed broadcast ephemeris data available from the Crustal Dynamics Data Information System (CDDIS)
  • Format: RINEX V2, UNIX compressed ASCII
  • Spatial Coverage: 90.0 to -90.0, 180.0 to -180.0
  • Temporal Coverage: 1992-01-01 to present
  • Temporal Resolution: Daily
  • File Size: 2.5 Mbytes/site/day
  • Platforms: Multiple GNSS

Description

GNSS receivers collect the signals from orbiting satellites to determine their location in three dimensions and calculate precise time. GNSS receivers detect, decode, and process both pseudorange (code) and phase transmitted by the GNSS satellites. The satellites transmit the ranging codes on two or more radio-frequency carriers, allowing the locations of GNSS receivers to be determined with varying degrees of accuracy, depending on the receiver and post-processing of the data. The receivers also calculate current local time to high precision facilitating time synchronization applications.

This dataset consists of ground-based Global Navigation Satellite System (GNSS) Mixed Broadcast Ephemeris Data (daily files) from the NASA Crustal Dynamics Data Information System (CDDIS). GNSS satellites provide autonomous geo-spatial positioning with global coverage. GNSS data sets from ground receivers at the CDDIS consist primarily of the data from the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS). Since 2011, the CDDIS GNSS archive includes data from other GNSS (Europe's Galileo, China's Beidou, Japan's Quasi-Zenith Satellite System/QZSS, the Indian Regional Navigation Satellite System/IRNSS, and worldwide Satellite Based Augmentation Systems/SBASs), which are similar to the U.S. GPS in terms of the satellite constellation, orbits, and signal structure. The daily GNSS broadcast ephemeris files contain one day of mixed GNSS navigation (30-second sampling) data in RINEX format from a global permanent network of ground-based receivers, one file per site.

Data Access

The daily 30-second GNSS mixed broadcast ephemeris data are online:

in subdirectories by year, day of year, and data type as follows:

YYYY/DDD/YYp/XXXXMRCCC_K_YYYYDDDHHMM_01D_30S_MN.rnx.gz

Code Meaning
YYYY4-digit year
DDD 3-digit day of year
YY2-digit year
XXXX4-character IGS station name
Mmonument or marker number (0-9)
Rreceiver number (0-9)
CCCISO country code
KData source:

R = From Receiver data using vendor or other software
S = From data Stream (RTCM or other)
U = Unknown
HH 2-digit hour
MM 2-digit minute
.gz Compressed file

Documentation

https://cddis.nasa.gov/Data_and_Derived_Products/GNSS/daily_30second_data.html